Phase-locked loop circuits are used in high-speed communication devices to generate a continuous wave signal at a precise and stable frequency. Phase-locked loop circuits generally include a reference frequency, a synthesizer, and a voltage-controlled oscillator. A known synthesizer used in phase-locked loop circuits is a fractional N synthesizer. As its name suggests, a fractional N synthesizer which utilizes fractional levels of the reference frequency to synthesize an output frequency.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.